xwayland: do not include weston.h

weston.h is a Weston frontend header, while this is a libweston plugin. A
libweston plugin cannot depend on Weston. Luckily the header is not actually
needed.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

xwayland/launcher.c

@@ -40,7 +40,6 @@
 #include <libweston/xwayland-api.h>
 #include "shared/helpers.h"
 #include "shared/string-helpers.h"
-#include "compositor/weston.h"
 
 static int
 weston_xserver_handle_event(int listen_fd, uint32_t mask, void *data)